Thursday, 6 January 2005

Lots of consecutive political posts again. How come something truly major comes along, and after less than a week, it's inspired lots of politics?

So this isn't a political post. It's about Brains and Human Evolution. And Politics.

The 29 December 2004 issue of the journal Cell contain an article that analyses the latest research on genetics and the human brain. It contains something quite unexpected. Our higher brain functions evolved unusually rapidly, implying a most unusual evolutionary pressure at some time. Basically, at one point, times were tough, and only the Intellectual Olympians survived to breed. How do we know this? By close examination of genetic changes and subtle clues in various proteins. Not my field, I'll take the molecular biologists' word for it though.

Now intelligence is good, but it's not the be-all and end-all. Sometimes a good pair of running legs is a better guarantee of survival than the ability to read Shakespeare in the original Klingon. Presence of Mind is Good, but when the Tsunami comes, Absence of Body is better. Something other than the usual menace-of-Sabre-Tooth-Tigers must have been at work, and working overtime to get so much accomplished so quickly.

It is conjectured that the evolutionary pressure is due to... Sociology. Or to put it more bluntly, Politics. Interpersonal, intra- and inter-tribal. Homo Sapiens is, after all, the Political Animal. And we now have some objective, hard evidence that there really is something rather unique about our evolutionary development, despite the relatively small difference between our own Intellect and that of our closest relatives', the other two Chimpanzee species.

Generally speaking, the higher up the evolutionary tree, the bigger and more complex the brain becomes (after scaling to body size). But this moderate trend became a huge leap during human evolution. The human brain (pictured) is exceptionally larger and more complex than the brains of nonhuman primates, including man's closest relative, the chimpanzee
[...]
According to Lahn, data from the Cell paper secures humans' privileged position in the evolutionary tree. "Human brain evolution required a major overhaul of the genetic blueprint - perhaps much more so than the evolution of other biological traits," he said.

But how did human ancestors encounter an environment where selection for better brains suddenly became such a prominent force? Lahn suggests that because humans have become a progressively more social species, greater cognitive abilities have become more of an advantage.

"As humans become more social, differences in intelligence will translate into much greater differences in fitness," he said, "because you can manipulate your social structure to your advantage.

"Even devoid of the social context, as humans become more intelligent, it might create a situation where being a little smarter matters a lot.

"The making of the large human brain is not just the neurological equivalent of making a large antler. Rather, it required a level of selection that's unprecedented," Lahn said.

"Our study offers the first genetic evidence that humans occupy a unique position in the tree of life. Simply put, evolution has been working very hard to produce us humans."

About Me

Actually, I am a Rocket Scientist.
Also hormonally odd (my blood has 46xy chromosomes anyway) and for most of my life, I looked male, and lived as one, trying to be the best Man a Gal could be. Anyway, in May 2005 that started changing naturally for reasons still unclear, and I'm now Zoe, not Alan : happier and more relaxed not to have to pretend any more.
UPDATE - reason now identified as the 3BHSD form of CAH.

Reviews

This blog, written by a rocket scientist, is a fascinating collection of information, both personal and scientific, regarding intersex, transsexualism and related psychosocial and psychosexual issues....It is erudite and heartfelt. Just read the posts about the passport issue. You won't know whether to laugh, weep or crawl into a ball and rock gently in a corner - an amazing person.- David---The reason I so appreciate bright, perceptive people - as opposed to ideologues whose intelligence does little to illuminate - is that they manage to both instruct and learn with a certain grace. Among such rarities in the transblogosphere is Zoe, whose direct speech and clear humanity always make her worth reading, even if one doesn’t always agree with her every conclusion.- Val---The following is a request for permission to archive your A.E.Brain blog site which we have wanted to do for several years...The Library has traditionally collected items in print, but it is also committed to preserving electronic publications of lasting cultural value....Since (1996) we have been identifying online publications and archiving those that we consider have national significance....We would like to include A.E.Brain blog site in the PANDORA Archive...-Australian National Library